U.S. Defense Secretary Chuck Hagel is warning that ISIS is "an imminent threat that is beyond anything we've ever seen." With a number of high-profile events coming up in Baltimore, a local expert shed light on who this group is, how they're funded and what they want.

ISIS' success is pinned on a lack of resistance but they are barbaric beyond comprehension and negotiation is not an option.

"They have to be eliminated, they have to be annihilated, they have to be stopped," said Johns Hopkins University political science Professor Steven David, an expert on international security and terrorism.

"There is nothing to negotiate with these people. They themselves are not asking for negotiation. They want complete capitulation, they want to turn everyone into extreme Sunni fanatics and if you are not willing to do that, then you are dead," David said.

Experts said ISIS is a continuum of terrorist groups but what sets them apart is the large swath of territory they have conquered and declared as their Islamic state. Its roughly 10,000 members are using weaponry that the U.S. provided to the Iraqi army. ISIS also has millions of dollars at its disposal.

"European governments have provided millions of dollars in ransom, extortion, they've taken over banks in Iraq," David said.

Hagel warned ISIS is potentially a direct threat in the United States.

"ISIS is an imminent threat that is beyond anything we have ever seen," Hagel said.

The threat may elevate security concerns in Baltimore, which is hosting several high-profile events. Star-Spangled Spectacular is coming up, the Baltimore Orioles are marching toward a pennant and the start of the Baltimore Ravens season is just around the corner.

ISIS engages in a propaganda war using Twitter and other social media, prompting the State Department to troll for terrorists and wannabes daily through a Twitter account called Think Again, Turn Away. The effort targets fence-sitters.

David said the U.S. needs to supply the Kurds with better military equipment. The U.S. has been reluctant to do that because it would upset the Iraqi government.

"I think that's going to change now. We need boots on the ground, not necessarily American boots on the ground, but we need people in the Middle East who are willing and motivated to stop ISIS," David said.

ISIS is now threatening to execute a second American journalist and the group is calling for attacks on other American targets.